This invention relates to tile cutters and more specifically to cutters for ceramic tiles having one glazed major surface.
Cutting ceramic tiles to a desired size or shape is usually accomplished by first scoring the glazed surface of the tile with a wheel, disc, or blade well-known in the glass and ceramic cutting arts and thereafter applying pressure to the surface of the tile to cause the tile to fracture along the score line.
It is well-known to provide a tile cutter consisting of a yieldable support for the tile and a horizontal beam on which there is carried a cutting wheel to score a tile. An additional arm is provided to press against the top of the scored tile to cause it to fracture along the scored line. Such devices are shown in the patents issued to Engleke, U.S. Pat. No. 2,246,351 and Marus, No. 2,541,708. The penetration of the cutter in the direction of the tile is restricted in these patents by means of an adjustable screw acting as a stop. Other patents such as Postley, U.S. Pat. No. 1,873,721 and Fischer, No. 4,192,282, employ lateral fins or breaker arms secured to a handle which also holds the cutting tool to fracture the tile. The handles are l-shaped so that the breaker arms can be swung out of the way while the cutting tool is in operation and vice versa.
In order to reliably fracture a scored tile it is important that the breaker arms or their equivalent bear against the tile with a substantial bearing area and in a direction normal to the surface of the tile. When different thicknesses of tile are cut in the same device the Postley and Fischer patents do not fulfill these requirements. Other prior art devices such as the patents issued to Granite, U.S. Pat. Nos. 1,932,659 and 1,995,741 employ bell crank levers for bringing the cutting wheel into contact with the surface of the tile and thereafter bringing the breaking arm to bear against the tile surface. These structures are difficult from the standpoint of inserting and adjusting the tile positions and also in bringing the breaker arm into its proper position for dependable tile fracturing.
The present invention employs a simple linkage arrangement which shifts from a rectangular configuration during the scoring step to a paralelogram shape for tile breaking. The mere change in this position of the linkage automatically removes the cutting wheel or tool from the plane of the tile and presents the pressure member against the tile in the optimum position for various tile thicknesses.